There's a whole jargon connected with aerodynamics.
Many of them are best understood when explained in context.
I suggest getting a copy of Andy Lennon's "Basics of R/C Model Aircraft Design", from MAN, available from Amazon.com.
The terms commonly encountered in design and performance are illustrated nicely..
But for now,
"Moment" refers to a force applied to an object at a distance from some point on the object, or it relates an area's location to a point.
"moment coefficient" refers to the value of a number which describes how an airfoil responds to airflow around it,
and "washout" refers to a twist in a wing, from root to tip. This can be mechanical; the tip built with a twist in it, or aerodynamic, the twist being a result of choosing specific airfoils using their zero-lift lines to achieve "washout" without building it in.